Int J Sports Physiol Perform. 2021 May 1;16(5):682-687. doi: 10.1123/ijspp.2020-0191. Epub 2021 Feb 4.
The authors investigated the effect of foot cooling (FC) between sets in a leg press pyramid workout with resistance-trained participants.
A total of 12 resistance-trained men (age = 21.8 [0.6] y; training experience = 1.7 [1] y) performed a pyramid workout, including 4 sets of 85% to 90% 1-repetition maximum leg press exercise to exhaustion with interset FC or noncooling in a repeated-measures crossover design separated by 5 days. The authors immersed the participants' feet in 10°C water for 2.5 minutes between sets.
Two-way repeated-measures analysis of variance revealed that FC elicited significantly higher repetitions and electromyography (EMG) values of the vastus lateralis (simple main effect of condition) than did noncooling (P < .05) in the second (repetitions: 11 [3.5] vs 7.75 [3.2]; EMG: 63.4% [19.4%] vs 54.5% [18.4%]), third (repetitions: 8.9 [3.2] vs 6.4 [2.1]; EMG: 71.5% [17.4%] vs 60.6% [19.4%]), and fourth (repetitions: 7.5 [2.7] vs 5.1 [2.2]; EMG: 75.2% [19.6%] vs 59.3% [23.5%]) sets. The authors also detected a simple main effect of set in the FC and noncooling conditions on repetitions (P < .05) and in the FC condition on the vastus lateralis EMG values. Although the authors observed no time × trial interactions for the rating of perceived exertion, the authors observed main effects on the sets (7.7-9.6 vs 7.9-9.3, P < .05).
Interset FC provides an ergogenic effect on a leg press pyramid workout and may offset fatigue, as indicated by higher repetitions and EMG response, without increasing perceived exertion.
作者研究了在抗阻训练参与者的腿部按压金字塔训练中，组间脚部冷却（FC）对训练的影响。
共有 12 名抗阻训练男性（年龄=21.8[0.6]岁；训练经验=1.7[1]年）进行了一次金字塔训练，包括 4 组 85%至 90%的 1 次重复最大腿部按压运动，每组之间用 FC 或非冷却的方式进行间歇，采用重复测量交叉设计，间隔 5 天。作者将参与者的脚浸入 10°C 的水中 2.5 分钟。
双向重复测量方差分析显示，与非冷却相比，FC 引起的股外侧肌重复次数和肌电图（EMG）值显著更高（条件的简单主要效应，P<.05），第二组（重复次数：11[3.5]比 7.75[3.2]；EMG：63.4%[19.4%]比 54.5%[18.4%]）、第三组（重复次数：8.9[3.2]比 6.4[2.1]；EMG：71.5%[17.4%]比 60.6%[19.4%]）和第四组（重复次数：7.5[2.7]比 5.1[2.2]；EMG：75.2%[19.6%]比 59.3%[23.5%]）。作者还检测到 FC 和非冷却条件下股外侧肌 EMG 值的重复次数（P<.05）和 FC 条件下股外侧肌重复次数的简单主要效应。尽管作者没有观察到感觉用力评分的时间×试验交互作用，但作者观察到了组间的主要效应（7.7-9.6 比 7.9-9.3，P<.05）。
组间 FC 对腿部按压金字塔训练有促进作用，可能通过增加重复次数和肌电反应来抵消疲劳，而不会增加感觉用力。
